SQL Interview Questions In Tamil (2024)

SQL is a database language created by the scientists of IBM in 1970s.  It is used for accessing and manipulating data in databases. It stands for Structured Query Language. It is used to manage data bases like MySQL, Oracle, PostgreSQL, etc. SQL is one of the main topics covered in all technical job interviews conducted by top IT countries. In this article we will discuss some top SQL Interview Questions In Tamil.

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What is SQL?

SQL stands for Standard Query Language. SQL is a query language that helps computer to communicate with the databases. It is used to store, access, update and delete data in the databases. SQL makes use of commands and queries to communicate with the databases.

Benefits of  Using SQL

• Easy to Learn and Use: Simple syntax, user-friendly interface.
• Universality: Standardized language across different database systems.
• Powerful Querying: Complex queries for efficient data retrieval.
• Data Integrity: Enforces accuracy, consistency, and reliability.
• Scalability: Easily handles growing datasets and user loads.
• Security: Robust features for data protection and privacy.
• Data Manipulation: Insert, update, delete data operations.
• Data Analysis and Reporting: Extract insights, generate reports efficiently.

Limitations of SQL

• Performance: Complex queries can impact performance.
• Scalability: Challenges with scaling large databases.
• Compatibility: Limited compatibility across different database systems.
• Security: Vulnerabilities like SQL injection attacks.
• Transaction Control: Limited support for nested transactions.
• No Native Version Control: Lack of built-in version control.
• Steeper Learning Curve: Mastery requires time and practice.
• Lack of Standardization: Dialect differences among SQL implementations.

Uses of SQL in 2024

Learning SQL will be beneficial in 2024 for the following reasons:

Enhances Career Opportunities:

SQL skills are highly sought after in various industries, including IT, finance, healthcare, and e-commerce. This leads to an increased job prospects and career advancement opportunities.

Data Management:

SQL enables efficient management of large datasets. It makes it essential for roles involving data analysis, reporting, and decision-making.

Also Read : Data Sets for Analysis to Enhance Data Science Portfolio

Business Intelligence:

Understanding SQL facilitates the extraction of valuable insights from data. This aids in strategic planning and business intelligence initiatives.

Database Administration:

Proficiency in SQL is essential for managing and maintaining databases. This ensures data integrity, security, and performance.

Application Development:

 SQL knowledge is vital for developing applications that interact with databases. This enables functionalities such as data retrieval, storage, and manipulation.

Data-driven Decision Making:

SQL skills empower individuals to make informed decisions based on data analysis. This contributes to organizational success and innovation.

Collaboration:

Proficiency in SQL fosters collaboration with data analysts, developers, and stakeholders. This facilitates effective communication and problem-solving.

Flexibility:

SQL is a portable language used across various database platforms. This offers flexibility and versatility in career opportunities and project assignments.

SQL Interview Questions

1. What is SQL?

Ans. SQL (Structured Query Language) is a programming language used to manage and manipulate databases.

2. What is a database?

Ans: A database is a structured collection of data organized for efficient retrieval and manipulation.

3. What is a table in SQL?

Ans. A table in SQL is a collection of related data stored in rows and columns.

4. What is a primary key?

Ans. A primary key is a unique identifier for each record in a table. It makes sure that each row in a table is uniquely identifiable.

sql code

CREATE TABLE Students (

StudentID INT PRIMARY KEY,

Name VARCHAR(50),

Age INT

);

5. What is a foreign key?

 Ans. A foreign key is a column or set of columns in one table that references the primary key in another table, establishing a relationship between the two tables.

sql code

CREATE TABLE Orders (

OrderID INT PRIMARY KEY,

ProductID INT,

FOREIGN KEY (ProductID) REFERENCES Products(ProductID)

);

6. What is the difference between DELETE and TRUNCATE commands?

Ans.  DELETE command removes rows one by one, allowing rollback. TRUNCATE command removes all rows at once, cannot be rolled back, and resets identity columns.

sql code

DELETE FROM Students WHERE StudentID = 1;

TRUNCATE TABLE Students;

7. What is a JOIN clause?

 Ans. A JOIN clause is used to combine rows from two or more tables based on a related column between them.

sql code

SELECT Orders.OrderID, Customers.CustomerName

FROM Orders

INNER JOIN Customers ON Orders.CustomerID = Customers.CustomerID;

8. What is the difference between INNER JOIN and LEFT JOIN?

 Ans. INNER JOIN returns only the matching rows from both tables. LEFT JOIN returns all rows from the left table and matching rows from the right table.

 Sql  code

SELECT Orders.OrderID, Customers.CustomerName

FROM Orders

LEFT JOIN Customers ON Orders.CustomerID = Customers.CustomerID;

9. What is the WHERE clause used for?

Ans. The WHERE clause is used to filter records based on specified conditions.

Sql code

SELECT * FROM Customers WHERE Country = ‘USA’;

10. What is the ORDER BY clause used for?

Ans. The ORDER BY clause is used to sort the result set in ascending or descending order based on specified columns.

Sql code

SELECT * FROM Products ORDER BY Price DESC;

11. What is the GROUP BY clause used for?

Ans. The GROUP BY clause is used to group rows that have the same values into summary rows.

Sql  code

SELECT Department, COUNT(*) FROM Employees GROUP BY Department;

12. What is the HAVING clause used for?

Ans. The HAVING clause is used to filter groups returned by the GROUP BY clause.

Sql code

SELECT Department, COUNT(*) FROM Employees GROUP BY Department HAVING COUNT(*) > 5;

13. What is the COUNT() function used for?

 Ans. The COUNT() function is used to count the number of rows in a result set.

Sql code

SELECT COUNT(*) FROM Customers;

14. What is the MAX() function used for?

 Ans. The MAX() function is used to find the highest value in a column.

Sql  code

SELECT MAX(Price) FROM Products;

15. What is the SUM() function used for?

Ans. The SUM() function is used to calculate the sum of values in a column.

Sql  code

SELECT SUM(Quantity) FROM Orders;

16. What is the AVG() function used for?

Ans. The AVG() function is used to calculate the average value of a column.

Sql code

SELECT AVG(Price) FROM Products;

17. What is the DISTINCT keyword used for?

 Ans. The DISTINCT keyword is used to return only distinct (different) values in a column.

Sql  code

SELECT DISTINCT Country FROM Customers;

18. What is the LIKE operator used for?

 Ans. The LIKE operator is used to search for a specified pattern in a column.

Sql  code

SELECT * FROM Products WHERE ProductName LIKE ‘Ap%’;

19. What is the BETWEEN operator used for?

 Ans. The BETWEEN operator is used to select values within a specified range.

Sql code

SELECT * FROM Products WHERE Price BETWEEN 10 AND 20;

20. What is the LIMIT clause used for?

 Ans.  The LIMIT clause is used to limit the number of rows returned in a result set.

Sql code

SELECT * FROM Customers LIMIT 5;

SQL Interview Questions In Tamil (2024): Video

Given below are link to videos with TCS  Interview Questions In Tamil:

SQL Interview Questions In Tamil (2024): Conclusion

SQL is one of the most important topics that will be covered in most of the technical interview questions. Hence, make sure that you are well prepared with the SQL interview questions before you attempt the recruitment process of any IT company. This article share some important questions along with videos for the convenience of the candidates who understand Tamil.

SQL Interview Questions In Tamil (2024): FAQs?

1. Why learning SQL is important?

Ans. Learning SQL is important because it equips individuals with essential skills for effectively managing and manipulating data in databases. This enables efficient data retrieval, analysis, and reporting, which are crucial for decision-making processes and organizational success.

2. Which companies use SQL?

Ans. Many companies, including technology giants like Google, Microsoft, and Oracle, as well as financial institutions like JPMorgan Chase and healthcare organizations like Pfizer, rely on SQL for managing and analyzing their data.

3. What are the uses of SQL?

Ans. SQL is used for managing and querying databases, enabling tasks such as data manipulation, retrieval, and administration. It is essential for various applications, including data analysis, application development, and business intelligence, across industries.